Electromagnetic switch



1965 H. E. WHITING ETAL 3,222,475

ELECTROMAGNETIC SWITCH 2 Sheets-Sheet 1 Filed Aug. 16 1963 IN VEN TOR.HAROLD E WH/ TING (JORDAN F PUETZ BY c- 1965 H. E. WHITING ETAL3,222,476

ELECTROMAGNETIC SWITCH Filed Aug. 16, 1963 2 Sheets-Sheet 2 k 4s 74 7074 4a 70 4s 74 70 74 4s "I 26. 3 24 x I l I! I, -\I--| WM INVENTORHAROLD E. WH/T/NG JORDAN F. PUETZ United States Patent 3,222,476ELECTROMAGNETIC SWITCH Harold E. Whiting, Bayside, Milwaukee, and JordanF.

Puetz, Milwaukee, Wis., assignors t0 Square D Company, Park Ridge, Ill.,a corporation of Michigan Filed Aug. 16, 1963, Ser. No. 302,591 9Claims. (Cl. 200-104) The present invention relates to electricalswitching devices and is more particularly concerned with a novelarrangement and construction of the parts of an electromagneticswitching device which will provide an economical and reliable switchingdevice which can be serviced with minimum difficulty.

Electromagnetic switching devices usually are provided with a magnetmotor which includes a stationary magnet part, a coil and an armaturewhich is moved in response to magnet flux induced in the stationarymagnet and armature by current flow through the coil. The armaturefrequently is connected to a yoke which carries a plurality of movablecontact-s which are arranged to move relative to a plurality ofstationary contacts to either a circuit closing or a current openingposition upon movement of the armature.

The electromagnetic device according to the present invention isprovided with a base which supports the stationary contacts of thedevice with the stationary contacts being arranged as a plurality ofpairs of contacts, each pair being separated by partitions to provideadequate electrical clearance and arc isolation between adjacent pairsof contacts. The device also includes an assembly which comprises amagnet motor and a yoke which carries the movable contacts of thedevice. The yoke is arranged to be guided by portions of a cover for thedevice so the movable contacts will be properly guided as they engagethe stationary contacts.

It is an object of the present invention to provide an electricswitching device with a base which has a plurality of pairs of spacedstationary contacts oriented as pairs in parallel rows and withinsulating partitions separating the respective pairs from each otherand to provide the device with a movable contact assembly which includesa plurality of pairs of movable contacts which are arranged to be movedinto engagement with the stationary contacts upon energization of amagnet motor which is part of the assembly and which is positioned onthe base by a cover which encloses the assembly and is arranged to guidethe movable contacts into engagement with the stationary contacts.

It is another object of the present invention to provide a cover forelectric switching device with means for positioning a coil of anelectromagnet operator for the device on a base for the device and ameans for guiding the movable contacts of the device into engagementwith stationary contacts which are carried by the base.

In carrying out the above object it is another object of the presentinvention to secure the cover to the base and the coil to the base by apair of screws which engage a pair of U-shaped threaded members carriedby the base.

A further object of the present invention is to provide an electricswitching device with a base which positions a plurality of pairs ofstationary contacts, a movable contact assembly which includes a magnetmotor and a plurality of movable contacts which are arranged to be movedinto and from engagement with the stationary contacts by the magnetmotor, and a cover which is secured to the base and encloses the movablecontact assembly with an arrangement whereby slots in the end walls ofthe cover provide a guiding means for lugs on the ends of a yoke whichcarries the movable contacts of the switching device so the movablecontacts are guided 3,222,476 Patented Dec. 7, 1965 ice into engagementwith the stationary contacts and an arrangement whereby an armature ofthe magnet motor is secured to the yoke by a spring clip which isarranged to permit movement of the armature so proper engagement willoccur between the pole faces of the armature and a stationary magnetpart of the magnet motor when a coil of the magnet motor is energized.

In carrying out the foregoing object it is another object to form theyoke as a U-shaped part which has the movable contacts resilientlycarried on the bight portion of the part and wherein a pair of arms ofthe part extend from the bight portion on opposite sides of the coil andstationary magnet and wherein each of the arms is provided with anelongate opening to receive a spring for resiliently supporting the yokeon the base of the device and wherein each of the arms is provided witha support for the armature and a cylindrical end for receivingsocket-like arms of the clip which movably secures the armature to theyoke.

Further objects and features of the invention will be readily apparentto those skilled in the art from the specification and appended drawingillustrating certain preferred embodiments in which:

FIG. 1 is a top plan view of an electric switch incorporating thefeatures of the present invention.

FIG. 2 is a sectional view taken along line 22 in FIG. 1.

FIG. 3 is an exploded end view of the switch in FIG. 1.

FIG. 4 is an exploded side view of the switch in FIG. 1.

In the drawings, a switching device 10 is provided with a base 12, amovable contact assembly 14, and a cover 16. The base 12, which ispreferably formed of a suitable molded insulating material, may besecured to a member 18 by threaded screws 20. The member 18 is providedfor purposes of securing the switching device 10 to a suitable panel orother support.

The base 12 is provided with a central cavity which is divided by aplurality of parallel spaced partitions 22, one of which is shown partlyin section in FIG. 4. The partitions 22, each of which is provided witha central notch 36, are arranged to divide the cavity within the baseinto a plurality of spaced compartments, each of which has a pair ofspaced stationary contacts 24 located therein. The stationary contacts24 are each electrically connected with a terminal member 26 which arearranged to receive and secure a bared end of an electrical conductor.The terminal members 26 are located on the base external of the cover 16when the cover 16 is applied to the base 12 in the manner which will behereinafter described. The partitions 22 separate the stationarycontacts into parallel rows of stationary contacts as apparent fromFIGS. 2 and 4 of the drawings. The base 12 is also provided with a pairof bosses 28 which are located on the base as shown in FIGS. 2 and 4 ofthe drawings. The bosses 28 are arranged to receive a U- shaped clip 30.A bight portion 30a of the U-shaped clip has a pair of arms 3% and 300extending therefrom. The arm 30b is provided with a barb which isreceived in a recess in the boss 28 so as to anchor the clip 30 on theboss 28. The arm portion 300 is provided with a threaded opening 30daligned with an opening 32 in the boss 28 to receive the threads of ascrew 34, as will be hereinafter described.

The movable contact assembly 14 includes a magnet motor 38 having astationary magnet part 40, a coil 42 and an armature 44. The assembly 14also includes a yoke 46 which is preferably formed of a moldedinsulating material to carry a plurality of spaced movable contacts 48.The yoke 46 and armature 44 are removably ecured to each other by meansof a spring clip 50, which will be hereinafter described. The coil 42 ispreferably molded to have a slot 52 extending along its bottom surfaceto embrace a bight portion 54 of the stationary magnet part 40. The coil42 also has a pair of outwardly extending lugs 56 arranged to rest onthe upwardly extending portions 28 of the base 12 when the device isassembled. The lugs 56 are provided with suitably located apertures 42ato receive the screws 34 when the cover 16 is secured to the base 12 inthe manner which will be hereinafter described. Each of the lugs 56 hasa terminal 58 which is electrically connected to an end of the coilWinding and is arranged to be connected to a bared end of an electricalconductor. The coil 42 is provided with a rectangular central openingextending therethrough which receives a central leg of the stationarymagnet part 40 and a central leg 60 of the armature 44. The stationarymagnet part 40 and the armature 38 are both E-shaped and each have outerlegs 62, 64, respectively, providing pole faces which are engageablewith one another when the coil 42 is energized. The outer legs 62 and 64are disposed exterior to the coil 42 and are received between a pair ofarm portions 68 of the yoke 46. The yoke 46 has a bight portion 66connecting the arm portions 68 which is provided with a plurality ofspaced slots 70 that are arranged to pass in the notches 36 and straddlethe partitions 22 in the base 12. The notches 70 separate the bightportion 66 into a plurality of spaced movable contact supports which arearranged to extend downwardly into the compartments wherein thestationary contacts 24 are disposed. The movable contact supports aresuitably apertured to receive the movable contacts 48 and a spring 74which resiliently biases the movable contacts 48 downwardly as in FIG.4. Extending inwardly from each of the free ends of arm 68 is a ledge 76which has its top surface slightly rounded and arranged to engage aportion 78 of the armature. Extending upwardly from the ledge portion 76on the free end of each of the arms 68 is a knob 80 which is centeredaxially with the top of the rounded surface of ledge 76. The knobs 80each are arranged to receive a pair of curved arms which form a pair ofsockets 82 which extend downwardly from the opposite ends of the clip50. Positioned intermediate the sockets 82 and extending in the samedirection as the arms which provide the sockets 82 are a pair of arms 84which are arranged to tightly receive the external surfaces on oppositesides of the center of the armature 38 so as to secure the clip 50 tothe armature 44. Each of the arms 68 of the yoke 46 has an outwardlyVertically extending lug 86 ertending in opposite directions. The lugs86 are received in suitably located slots 89 in the cover 16.

The arms 68 also have vertically extending openings 88. A spring 90which is positioned in each of the openings 88 has one end seated on aseat 92 at one end of the openings 88 and engages a member 94 at theother end of the openings 88. The springs 90 urge the members 94 intoengagement with an insulating member 96. The ends of the insulatingmember 96 are suitably notched to embrace the arms 68 as the midportionof member 96 rests upon the bight portion 66, of the yoke 46. Thenotched end portions of the insulating member 96 are arranged to restupon ledges at the opposite end surfaces of the cavity within the base12 so as to resiliently support the yoke on the base when the base andyoke are assem bled. A rubber-like strip member 98 is positioned betweenthe stationary magnet part 40 and the member 96.

The cover 12 is preferably formed of a suitable molded material and hasa pair of openings 16a which are located to receive the screw 34 forsecuring the cover 16 to the base 12. The cover is provided with notches99 which receive the bosses 28 on the base 12 and an opening 160 whichwill permit observation of the armature 44 when the parts are assembledto determine whether or not the device is in the energized orde-energized condition. Preferably, one of the walls of the slots 89 inthe cover 12 is covered with a metal surface 102, so that the lugs 86which are formed of insulating material, will engage a metal surface andminimize wear of the device in service.

In view of the foregoing description, the assembly of the device will behereinafter set forth. The base 12, including the stationary contacts 24which are connected to the terminal members 26 and the clips 30 whichare secured in position on lugs 28, is secured to the member 18 by bolts20. An assembly comprising the yoke 46, the movable contacts 48, thespring 74, the insulating member 96, the members 94 and springs 90, isassembled with the stationary magnet part 40 which has the resilientbumper 98 secured along the bottom surface and in engagement with themember 96. The coil 42 is then placed over the central lugs of thestationary magnet part with the slots 52 receiving the bight portion ofthe stationary magnet part 48. The clip 50 is also assembled with thearmature 44 by inserting the center of the bight portion of the armature44 between the spaced arms 84 of the clip 50. The assembly, includingthe clip 50 and armature 44, is then positioned on the yoke 46 bycausing the resilient arms which provide the sockets 82 to engage theknobs on the yoke. When this connection is accomplished, the roundedsurface provided by the ledges 76 and the rounded surface provided bythe knobs 80 will permit the armature 44 to have a limited rockingmotion relative to the yoke 46 so as to permit firm seating between thepole face of the armature 44 and the stationary magnet part 48 when thecoil 42 is energized. The movable contact assembly 14, which includesthe yoke 46, the coil 42, the stationary magnet part 40, the armature 44and clip 56, is then assembled with the base 12. When the base andmovable contact assembly are combined, the lugs 56 on the coil arepositioned on the portions 28 of the base and the insulating member 94rests upon ledge portions of the base to support the stationary magnetpart on the base. After the base 12 and movable contact assembly 14 arethus assembled, the cover 16 is then positioned on the base 12 tocompletely enclose the movable contact assembly 14. The cover 16 andcoil 42 are secured to the base by means of the screws 34 which extendthrough the openings 16a in the cover, the opening 42a in the lug 56 andthe opening 32 in the boss 28 into the threaded openings 30d of the clip30. When the cover 16 is thus secured, the slots 89 will receive lugs 86and act as a guide means to vertically guide the yoke 46 of the movablecontact assembly 14 when the magnet motor is energized to move themovable contacts 48 into bridging engagement with the pairs of spacedstationary contacts 24 on the base 12.

While certain preferred embodiments of the invention have beenspecifically disclosed, it is understood that the invention is notlimited thereto, as many variations will be readily apparent to thoseskilled in the art and the invention is to be given its broadestpossible interpretation within the terms of the following claims:

What is claimed is:

1. In an electric switching device, an insulating base having aplurality of pairs of spaced stationary contacts oriented as pairs inparallel rows on the base and insulating partitions separating each ofsaid pairs from an adjacent pair of stationary contacts, a movablecontact assembly including movable contacts and a magnet motor removableas a unit from the base and a cover enclosing the movable contactassembly and having portions engaging with portions of the magnet motorpositioning the magnet motor on the base and slots engaging portions ofthe movable contact assembly guiding the movable contacts of saidassembly into engagement with the stationary contacts.

2. The combination as recited in claim 1 wherein the movable contactassembly includes a yoke formed of insulating material having spacedopenings positioning a plurality of movable contacts which are spacedand oriented to bridgingly engage the pairs of stationary contacts onthe base, and the portions of magnet motor engaged by the cover areprovided by oppositely extending terminal portions on a magnet coilwhich are held in position on a portion of the base by the cover.

3. The combination as recited in claim 2 wherein the yoke includes apair of lugs extending in opposite directions which are received in theslots in the cover for guiding the movable contacts into engagement withthe stationary contacts.

4. The combination as recited in claim 1 wherein the magnet motorincludes: an E-shaped stationary magnet, a coil having a central openingreceiving a central leg of the E-shaped stationary magnet and immovablypositioning the stationary magnet on the base when the coil is securedto the base, an E-shaped armature having an inner leg received withinthe opening of the coil and a pair of outer legs arranged to engage apair of outer legs of the stationary magnet upon energization of thecoil, an elongate carrier having; a plurality of openings positioningthe movable contacts, a pair of guides extending in opposite directionsmovable in the slots in the cover and means including a pair of spacedrounded ledges supporting the armature on the carrier and a spring clipengaging the armature and carrier for maintaining the armature on therounded ledges.

5. The combination as recited in claim 4 wherein the carrier has a pairof spaced rounded lugs and the spring clip is provided with a pair ofspaced resilient arms at each end of the clip for receiving the roundedlugs and a pair of spaced resilient arms intermediate its ends forresiliently securing the armature to the clip.

6. The combination as recited in claim 1 wherein a pair of U-shapedclips carried by the base have threaded openings for a pair of screwsfor securing the cover to the base.

7. In an electric switching device the combination comprising; aninsulating base having opposed end walls, opposed side walls, a bottomwall and a plurality of spaced partitions extending between the bottomand side walls and parallel to the end walls providing a plurality ofspaced compartments, a pair of spaced stationary contacts in each ofsaid compartments spaced on opposite sides of a center line, a guide wayin each of the end walls extending normal to the bottom wall along anaxis extending through the center line, an insulating member having apair of spaced parallel arms extending from an interconnecting bightportion, said arms being spaced for receipt in the guide ways forguiding movement of the bight portion along an axis normal to the bottomwall into juxtaposition with the bottom wall, a plurality of movablecontacts carried by the bight portion and spaced to be received in thecompartments and bridgingly engage the stationary contacts in thecompartments when the insulating member and bottom wall are injuxtaposition, a ledge on a free end of each of the arms of theinsulating member extending inwardly toward each other and having arounded surface facing away from the bight portion, a knob on the freeend of each arm of the insulating member, and a guide on the free end ofeach of the arms of the insulating member extending in oppositedirections from each other, a resilient means operative between the baseand arms for constantly urging the bight portion of the insulatingmember out of juxtaposition with the bottom wall, a magnet motor havingan E-shaped stationary magnet supported on the base and received betweenthe arms of the insulating member, a coil having a central opening forreceiving a central leg of the E-shaped stationary magnet and an E-shaped armature having portions resting on the ledges of the arms of theinsulating member and having an inner leg received within the opening ofthe coil and a pair of outer legs disposed external to the coil andarranged to engage a pair of outer legs of the stationary magnet uponenergization of the coil, a resilient elongate clip having a pair ofspaced resilient arms at each end embracing the knobs on the arms of theinsulating member and a pair of spaced resilient arms intermediate theends of the clip embracing the armature for resiliently and rockinglysecuring the armature to the insulating member, and a cover having aportion engageable with portions of the coil for positioning the coil onthe base and a pair of slots receiving the guides on the arms of theinsulating member for guiding the free ends of the arms of theinsulating member during movement of the bight portion of the insulatingmember toward the base.

8. The combination as recited in claim 7 wherein the base is providedwith a pair of U-shaped clips which are disposed on opposite sides ofthe base and are provided with threaded openings for receiving athreaded member extending through the cover and the coil portions forsecuring the cover and coil on the base.

9. In an electric switching device having stationary contacts, movablecontacts and a magnet motor assembly for moving the movable contactsinto engagement with the stationary contacts, said magnet motor assemblycomprising; a U-shaped insulating member having a pair of spacedparallel arms extending from opposite ends of a bight portion, means forresiliently supporting the movable contacts on the bight portion, aledge on an inner surface of a free end of each of said arms, a roundedsurface on each of said ledges facing away from the bight portion and aknob on the free end extremity of each arm, a magnet motor having acoil, a stationary magnet part and an armature having portionsengageable with the stationary magnet upon energization of the coil andportions resting on the rounded surface of the ledges, a resilientconnection between the stationary magnet and the insulating member, anda spring clip providing a connection between the insulating member andarmature, said clip having a pair of spaced arms located intermediatethe ends of the clip embracing opposite sides of the armature providingan immovable connection between the clip and armature and a pair ofspaced arms at each end of the clip arranged to provide a socketconnection with the knobs on the ends of the arms of the insulatingmember whereby the armature is pivotally supported on the insulatingmember to permit the engaging portions of the armature to firmly seat onthe stationary magnet upon energization of the coil.

References Cited by the Examiner UNITED STATES PATENTS 2,897,316 7/1959Brauneck 200-104 2,924,685 2/1960 Burch ZOO-T04 3,042,774 7/ 1962Hawkins 200104 BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCHAEFER, Examiner.

1. IN AN ELECTRIC SWITCHING DEVICE, AN INSULATING BASE HAVING APLURALITY OF PAIRS OF SPACED STATIONARY CONTACTS ORIENTED AS PAIRS INPARALLEL ROWS ON THE BASE AND INSULATING PARTITIONS SEPARATING EACH OFSAID PAIRS FROM AN ADJACENT PAIR OF STATIONARY CONTACTS, A MOVABLECONTACT ASSEMBLY INCLUDING MOVABLE CONTACTS AND A MAGNET MOTOR REMOVABLEAS A UNIT FROM THE BASE AND A COVER ENCLOSING THE MOVABLE CONTACTASSEMBLY AND HAVING PORTIONS ENGAGING WITH PORTIONS OF THE MAGNET MOTORPOSITIONING THE MAGNET MOTOR ON THE BASE AND SLOTS ENGAGING PORTIONS OFTHE MOVABLE CONTACT ASSEMBLY GUIDING THE MOVABLE CONTACTS OF SAIDASSEMBLY INTO ENGAGEMENT WITH THE STATIONARY CONTACTS.